The invention relates to a mechanical adjustment assembly and to systems adjusted thereby. In particular a mechanical adjustment assembly for use in systems comprising a series of mechanically interlinked components, in particular systems having components in difficult to approach environments such as but not limited to lithography systems, more in particular systems or mechanical arrangements comprising a frame, a first module connected to said frame, a second module carried by or connected to said frame.
The adjustment assembly according to the invention may be utilized for adjusting e.g. the position of such a second and first module with respect to one another. The system according to the invention is henceforth exemplified, but not limited to, a substrate exposure system comprising a substrate support module and an exposure apparatus, which are connected to a frame. Examples of such substrate exposure systems are lithography systems and inspection systems. The invention further relates to a method for adjusting the position of the exposure apparatus with respect to the substrate support module.
Lithography systems are arranged for projecting a pattern onto target which is usually a flat substrate, such as a silicon wafer. State of the art lithography systems expose the target by means of electromagnetic radiation, in particular light, more in particular UV light, or by means of charged particles, in particular electrons, for projecting said pattern on the flat substrate.
Inspection systems are arranged for exposing a target or sample by means of electromagnetic radiation, in a light microscope, or by means of charged particles, in particular electrons in an electron microscope, and analyzing the absorbed, reflected or emitted radiation or charged particles in order to acquire information from the target.
WO 2013/034753, for example, describes a lithography system, in particular a charged particle multi-beam lithography system, comprising a beam generator for generating a plurality of beams, a beam modulator for modulating the individual beams according to a desired pattern, and a beam projector for projecting the modulated beams onto a surface of a target which is arranged on a target positioning system. The components of a lithography or inspection system for generating and projecting the beams, whether they are charged particle beams, optical beams, or other types of beams, are typically arranged in a column and are usually referred to as the electron-optical column or optical column, and will be referred to herein as the ‘exposure apparatus’.
In addition, a lithography or inspection system comprises a substrate support module for holding a substrate at least during an exposure by the exposure apparatus. The substrate support module typically comprises a stage for moving the substrate with respect to the exposure apparatus, a chuck arranged on top of the stage, and a substrate support structure on top of said chuck, as described in WO 2013/034753.
The substrate exposure system as described in WO 2013/034753 comprises a support frame and a support element for holding the exposure apparatus. The support element is connected to the support frame by means of at least one spring element. As described in WO 2013/034753, the spring element is part of a module for at least partially isolating the support element from vibrations.
A disadvantage of the known system is that in use and over time, creep can occur inter alia in the spring element, which results in a deviation of the position of the support element with respect to the support frame from the set position. As a consequence, the position of the support element, and the position of the exposure apparatus held by said support element, with respect to the target on the target positioning system can also deviate from an optimum position in the system. This has an adverse effect on the performance of the system, specifically the exposure of targets.
Another exposure apparatus is known from US2009/0086178. This known system comprises a light source and an illumination optical system which illuminates a reticle. A barrel shaped projection optical system projects an image of the reticle onto a substrate on a wafer stage. The projection optical system is connected to a frame by means of three suspension support mechanism. Three drive mechanism are provided between the frame and projection optical system. Each drive mechanism includes a voice coil motor that drives the projection optical system in a radius direction of the barrel, and a voice coil motor that drives the projection optical system in the direction of an optical axis (the Z-axis direction). With three drive mechanisms, the projection optical system can be moved in the direction of six degrees of freedom.
A disadvantage of this known system is that the actuators which move the exposure apparatus are included as contactless motors and are thus limited in the load that can be carried.
A further disadvantage of substrate exposure systems in general, and lithography or microscopy systems in particular, is that they are highly complex systems in which a large number of components are arranged in a compact and/or enclosed configuration. In such systems it is difficult to adjust the position of a component, in particular when the component is not readily reachable from the outside of the system.
It is an object of the present invention to overcome or at least minimize the effect of one or more of these disadvantages or to at least provide a substrate exposure device comprising an alternative adjustment assembly and/or method for adjusting the position of a component of said substrate exposure device.